Various forms of saw chain tooth sharpeners have been heretofore provided. Some sharpners are designed to be manually operated and other sharpeners include powered rotary grinding wheels. The previously known sharpeners incorporating powered rotary grinding wheels are often provided with saw chain support structure and rotary grinding wheel support structure including features whereby the teeth on opposite sides of an associated saw chain may be alternately sharpened. In addition, most powered rotary grinding wheel equipped saw chain tooth sharpeners include structure whereby all of the teeth on each side of the chain may be similarly sharpened.
Of those previously known forms of powered rotary grinding wheel equipped saw chain sharpeners, the sharpener disclosed in my prior U.S. Pat. No. 4,104,793, dated Aug. 8, 1978, is closest in construction and operation to the improved form of saw chain sharpener of the instant invention.